Drill stem testing device



0 M12105! H. E. DRILL STEM TESTING DEVICE Filed Oct. 20, 1952 30 JNVENTOR. H.E. Schwegman,

ATTORNEY.

DRILL STEM TESTING DEVICE Harry E. Schwegman, Duncan, kla., assignor to Halliburton Oil Well Cementing Company, Duncan, Okla.

Application October 20, 1952, Serial No. 315,7 87

2 Claims. (Cl. 166-145) This invention relates to drill stem testing of oil wells and more particularly to an assembly whereby fewer operations are necessary to make the test.

The testing of oil wells or the like is now a highly developed art. Reference may be had to the patent of Simmons, No. 1,930,987, issued October 17, 1933, for a general understanding of the art to which the present invention relates.

In accordance with the present invention the assembly, consisting of a packer of any suitable design and a tester tool, is lowered into a well bore on drill pipe 'or the like. During the passage of the assembly into the well, fluid may by-pass the packer. When the packer is seated, the tester valve may be opened and the by-pass closed by merely lowering the drill pipe, but this action is retarded for a certain period of time by the employment of restricted passageways controlling the flow of a liquid from one chamber to another within the tester tool, so as to provide a construction by which bridges may hep'assed, the packer or anchor pipe spudded or other operations performed without danger of prematurely opening the tester valve proper, or prematurely closing the by-pass for the packer.

An important feature of the invention is the use of metering pins for restricting the liquid passageways so as to enable thousands of pounds of pressure to be exerted downwardly upon the tester tool for short periods of time without opening the tester valve or closing the bypass valve.

When the test is completed, the tester valve may be closed and the by-pass valve opened rapidly by merely picking up the drill pipe, this action being brought about by the use of a one-way O-ring valve structure which provides a conduit for shunting the metering pin passage ways.

The objects of the invention will be more apparent from consideration of the following detailed description, taken in connection with the accompanying drawings in which:

Figure l is a view in side elevation of an assembly which includes the present invention being lowered into a well bore;

Figure 2 is a view in vertical cross-section of the tester tool of Figure 1, the parts being shown in the position they occupy as the tool is being lowered into the well;

Figure 3 is a view similar to that of Figure 2 but showing the parts in the position they occupy when the by-pass is closed and the tester valve open;

Figure 4 is a view in perspective of one of the metering pins used in the tester tool of Figures 1 to 3;

Figure 5 is a view in transverse cross-section of the tester tool of Figures 1 to 3, the view being taken on the lines 55 of Figure 2.

Referring to the drawing in detail, it will be seen that a well bore is illustrated at 11 in Figure 1 and that an assembly consisting of a drill pipe 12, a testing tool 13, a packer 14, and an anchor pipe 15, is located therein. The present invention is concerned with the construction ted States Patent 0 of the testing tool 13, which is shown in detail in Figures 2 to 5, and which is provided with box and pin threads 16 and 17 at its upper and lower ends to make connection to the drill pipe and packer respectively.

In actual construction the tester tool 13 is made up of a number of parts connected together by screw threads but to simplify the drawing these have largely been eliminated in illustrating so as to make the arrangement easier to understand.

As shown in Figures 2 and 3, the tester tool includes two main parts, an inner mandrel 18 made integral with the upper connecting box 16 and an outer cylinder 19 made integral with the lower packer connecting pin 17.

The mandrel 18 acts somewhat as a piston within the cylinder 19. That is, relative sliding movement is permitted, but shoulders 20 and 21 are provided to prevent complete separation. Also, splines 22 are provided so that the mandrel cannot turn within the cylinder.

A heavy coil compression spring 23 may be provided as illustrated to urge the mandrel 18 upwardly out of the cylinder 19. This spring 23 is not necessary, perhaps, but it assists in closing the tester valve and is a safety feature. 1

There are two main valves controlled by longitudinal movement of the mandrel 18 within the cylinder 19. One is the tester valve which is provided by the ports 24 in a liner 25 made integralwith the cylinder 19 and the plunger 26 on the mandrel 18. It will be observed that there is a central conduit 27 extending down through a large part of the mandrel 18, but terminating above the plunger 26, and provided with branches 28. Similarly the cylinder 19 has conduits 29 at its lower end. Hence, when the plunger 26 is below the ports 24, fluid can flow from the anchor pipe 15, up through the packer 14, the conduits 29, and the ports 24, to enter the mandrel through the branches 28 and pass up through the conduit 27 into the drill pipe 12 to make the test. When the mandrel 18 is lowered in the cylinder, this tester valve is opened. When it is raised, it is closed.

The other main valve controlled by movement of the mandrel 18 in the cylinder 19 is the by-pass valve for the packer. It works the opposite of the tester valve. When the mandrel is lowered, it is closed, and when the mandrel is raised, it is opened. This bypass valve is provided by a body 30 on the mandrel 18 and a seat 31 near the bottom of the cylinder 19. In addition, a rubber cylindrical packing member 32 enters the lower bore 33 of the cylinder 19 when the mandrel 18 is lowered to eifect a double seal. A conduit 34 in the wall of the cylinder 19 permits fluid to flow from the anchor pipe 15 through the packer 14 and to the outside of the tester tool 13 when the by-pass valve is open.

In lowering the assembly into the well bore, the parts remain in the position shown in Figure 2 in which the tester valve is closed and the by-pass valve open. For satisfactory operation the positions of these valves should not be changed even if a bridge is struck or while spudding in the anchor pipe. The spring 23 mentioned above tends to keep the parts in the positions shown in Figure 2, but it cannot be relied upon to support very much weight and sometimes thousands of pounds must be exerted on the tool to force it on down into the well bore. (In one case 30,000 pounds of drill pipe were placed on the tester of the present invention and it did not open for 2 minutes and 10 seconds.)

To provide means for holding the parts in this position of Figure 2, even when such heavy loads are placed upon the tool, a special control arrangement has been provided. The annular space between the outside of the mandrel 18 and the inside of the cylinder 19 is sealed by packing rings, those at the top of the cylinder 19 being designated 35 and those at the bottom being designated 36. This annular space may, for convenience, be referred to as including two chambers designated A and B, separated by a one-way O-ring valve device 37. These chambers contain an oil or other liquid which is preferably little atlected by changes in temperature. Silicon oil of high viscosity has been used satisfactorily.

The object of these chambers A and B and associated structure, with the sealed in oil, is to retard downward movement of the mandrel 18 in the cylinder 19, in the extreme, and to permit the mandrel to move upwardly within the cylinder with ease.

The O-ring check valve 37 is such that no oil can flow upwardly past it while there is downward motion of the mandrel 18 within the cylinder. O-ring itself is movable but the portion of the mandrel about which it is confined by the spider 3% is taperedas illustrated at 39 so that when. the mandrel moves downwardly, the O-ring is wedged out into sealingengagement with the wall of the cylinder 19 as shownin Figure 2.

On the other hand, the O-ring 37 moves down against the spider 38, as shown in Figure 3, so that the oil can. then readily flow past the O-ring from chamber B into chamber A. For clarityin illustration, the O-ring is shown in upward or sealing position in Figure 2 and in its downward or open position in Figure 3, although the O-ring will not necessarily be in these particular positions when the mandrel 18 and cylinder 19 are in the respective positions shown in the figures.

The arrangement must be such that some oil will flow, although at an extremely slow rate considering the pressure, from chamber A into chamber B when the mandrel 18 is being lowered into the cylinder '19, for otherwise the tester valve could not be opened nor the by-pass valve closed.

To provide for this restricted flow the vertical passageways 40 and 41 are provided'inthe mandrel 18 and into when the mandrel 18 is raised, i

The rubber it is picked up, the oil flows from the chamber B into the chamber A so the parts resume the position illustrated in Figure 2.

When the packer is seated, weight is placed on the tool and allowed to remain a suflicient length of time, say 3 to 5 minutes, depending on the weight, the viscosity of the oil in the chambers, etc., to allow the tester valve to open and the by-pass valve to close. When the test is completed, the drill pipe is picked up which causes the tester valve to close automatically. While only one embodiment of the invention is shown anddescribed herein, it is obvious that various changes may be made without departing from the spirit of the inventionor the scope of the annexed claims.

I claim;-

1. In an oil well testing device, incombination with a drill pipe and packer, a testing tool consisting of a cylinder, a mandrel fitted within the cylinder for sliding longitudinal movement with respect'thereto and extending which metering pins 42 are inserted. A portion of one of the metering pins is shown in Figure 4. As shown, these metering pins are not spiral, but consist of solid rods upon which a number of rings or lands have been turned. They are fitted within the passageways and 41 with only a few thousandths of an inch clearance and are remarkably eifective'in retarding the flow of oil through the passage.

ways at the high pressures to which the oil is subjected while permitting gradual flow.

The top of the passageway 40 is connected to chamber A by the lateral 43. The top of passageway 41 is connected to the chamber B by the lateral 44. The bottoms of passageways 4t) and 41 are connected to each other a by a circular conduit 45 as shown in Figure 5.

The flow through these passageways is always in one direction, from the chamber A through the lateral 43, the passageway 40, the circular conduit 45, the passageway 41, and the lateral 4-4 to the chamber B. This flow occurs only while the mandrel 18 is being lowered through the cylinder 19 for a portion of the length of travel.

When the mandrel approaches the end of its downward movement, the O-ring 37 passes a small passageway 46 in the wall of the cylinder 19 near the bottom of the chamber A and the mandrel thenv jars on down suddenly since the O-ring check valve is then by-passed. This sudden jar causes the drill pipe and elevators to Shake and is a signal to the operator that the ,parts have taken the position shown in Figure 3 in which the tester valve is open.

The operation of the testing tool of the present invenupwardly out of the cylinder, connections for securing the mandrel to the drill pipe and for securing the cylinder to a packer, a tester valve and a packer bypass valve associated with the cylinder and actuated by longitudinal movement of the mandrel therein, the tester valve being closed and the by-pass valve being open when the mandrel is in its upward position with respect to the cylinder and the tester valve being open and the by-passvalve being closed when the mandrel is in its downward position with respect-to the cylinder, means for retarding the downward movement of. said mandrel within said cylinder including means providing a pair of chambers between the cyl nder and mandrel and a restricted passageway interconnecting them, through which oil or other liquid 0 has to flow to permit the mandrel to move downwardly in the cylinder, said restricted passageway having a metering pin therein having closely fittedlands thereon, and means including an O-ring check valve between the pair of chambers actuated by longitudinal movement of the mandrel within-.the cylinder for selectively shunting said rmtricted' passageway, the check valve being closed when the mandrel is moved downwardly with respect to the cylinder whereby said downward movement is a function of the-flow of liquid through said restricted passageway, and the check valve being open when the mandrel. is moved upwardly'with respect to the cylinder whereby said upward movement is a function of the fiow of liquid through said check valve and is substantially independent Rcferences Cited. in the file of this patent UNITED STATES PATENTS 1,788,109 Jett Jan. 6, 1931 2,077,760 Knoerr Apr. 20, 1937 2,122,080 Wisdom a. June 28, 1938 2,567,321 Courter Sept. 11, 1951 

